On top of the Mayler which carries metal dome contacts, silver paste or silver carbon paste is printed as ESD (Electrostatic Discharge Control). This helps reduce electrostatic which might be harmful to other parts inside of mobile phones. Electrostatic is gathered on the printed silver paste or silver carbon paste and neutralized.
EMI Single layer-- EMI is printed on top of single-layer metal dome arrays (dome arrays)
EMI Double layer-- EMI is printed on top of double-layer metal dome arrays (dome arrays)
Light & small
Damp proof, heatproof, cold proof
Dustproof is done on the Metal Dome, and oxygenation of Metal Dome has been avoided